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Abstract:

Disclosed herein is a light stabilized copolyetherester composition that
is substantially free of carbon black, and wherein the copolyetherester
composition comprises, based on the total weight of the copolyetherester
composition, (a) about 90-98.8 wt. % of at least one copolyetherester,
(b) about 0.1-2 wt. % of at least one organic UV absorber selected from
benzotriazole based UV absorbers and benzophenone based UV absorber, (c)
about 0.1-2 wt. % of at least one hindered amine light stabilizer, and
(d) about 1-6 wt. % of at least one mineral filler comprising mineral
particles selected from the group consisting of titanium dioxide
particles, cerium oxide particles, zinc oxide particles, and mixtures of
two or more thereof.

Claims:

1. A light stabilized copolyetherester composition that is substantially
free of carbon black, wherein the copolyetherester composition comprises,
based on the total weight of the copolyetherester composition, (a) about
90-98.8 wt. % of at least one copolyetherester, (b) about 0.1-2 wt. % of
at least one organic UV absorber selected from the group consisting of
benzotriazole based UV absorbers and benzophenone based UV absorber, (c)
about 0.1-2 wt. % of at least one hindered amine light stabilizer, and
(d) about 1-6 wt. % of at least one mineral filler comprising mineral
particles selected from the group consisting of titanium dioxide
particles, cerium oxide particles, zinc oxide particles, and mixtures of
two or more thereof.

2. A light stabilized copolyetherester composition of claim 1, wherein,
the at least one copolyetherester comprises a multiplicity of recurring
long-chain ester units and recurring short-chain ester units joined
head-to-tail through ester linkages, the long-chain ester units being
represented by formula (I): ##STR00006## and the short-chain ester
units being represented by formula (II): ##STR00007## wherein, G is a
divalent radical remaining after the removal of terminal hydroxyl groups
from a poly(alkylene oxide) glycol having a number average molecular
weight of about 400-6000; R is a divalent radical remaining after the
removal of carboxyl groups from a dicarboxylic acid having a number
average molecular weight of about 300 or lower; and D is a divalent
radical remaining after the removal of hydroxyl groups from a glycol
having a molecular weight of about 250 or lower, and wherein, based on
the total weight of the at least one copolyetherester, the recurring
long-chain ester units and the recurring short-chain ester units are
present in amounts of about 1-85 wt % and about 15-99 wt %, respectively.

3. A light stabilized copolyetherester composition of claim 1, wherein
the mineral particles have a weight average particle diameter of about
10-200 nm.

6. A light stabilized copolyetherester composition of claim 5, wherein
the organic coatings comprise a material selected from the group
consisting of carboxylic acids, polyols, alkanolamines, silicon
compounds, and mixtures of two or more thereof.

7. A light stabilized copolyetherester composition of claim 5, wherein
the inorganic coatings comprise a material selected from the group
consisting of oxides and hydrous oxides of silicon, aluminum, zirconium,
phosphorous, zinc, rare earth elements, and mixtures of two or more
thereof.

9. A light stabilized copolyetherester composition of claim 1, wherein
the at least one mineral filler comprises titanium dioxide particles
having a weight average particle diameter of about 10-200 nm.

11. A light stabilized copolyetherester composition of claim 1, wherein
the at least one organic UV absorber is selected from the group
consisting of benzotriazole based UV absorbers.

12. A light stabilized copolyetherester composition of claim 1, wherein,
based on the total weight of the copolyetherester composition, the
copolyetherester composition comprises about 90-98.8 wt. % of the at
least one copolyetherester, about 0.1-2 wt. % of the at least one organic
UV absorber, about 0.1-2 wt. % of the at least one hindered amine light
stabilizer, and about 1-6 wt. % of the mineral filler.

13. A light stabilized copolyetherester composition of claim 1, wherein,
based on the total weight of the copolyetherester composition, the
copolyetherester composition comprises about 92-98.8 wt. % of the at
least one copolyetherester, about 0.1-1 wt. % of the at least one organic
UV absorber, about 0.1-1 wt. % of the at least one hindered amine light
stabilizer, and about 1-6 wt. % of the mineral filler.

14. A light stabilized copolyetherester composition of claim 1, wherein,
based on the total weight of the copolyetherester composition, the
copolyetherester composition comprises about 92-98.6 wt. % of the at
least one copolyetherester, about 0.1-0.6 wt. % of the at least one
organic UV absorber, about 0.1-0.6 wt. % of the at least one hindered
amine light stabilizer, and about 1-6 wt. % of the mineral filler.

15. A light stabilized copolyetherester composition of claim 1, wherein,
based on the total weight of the copolyetherester composition, the
copolyetherester composition comprises about 92-97.8 wt. % of the at
least one copolyetherester, about 0.1-1 wt. % of the at least one organic
UV absorber, about 0.1-1 wt. % of the at least one hindered amine light
stabilizer, and about 2-6 wt. % of the mineral filler.

16. A light stabilized copolyetherester composition of claim 1, wherein,
based on the total weight of the copolyetherester composition, the
copolyetherester composition comprises about 92-95.8 wt. % of the at
least one copolyetherester, about 0.1-1 wt. % of the at least one organic
UV absorber, about 0.1-1 wt. % of the at least one hindered amine light
stabilizer, and about 4-6 wt. % of the mineral filler.

17. A light stabilized copolyetherester composition of claim 1, wherein,
based on the total weight of the copolyetherester composition, the
copolyetherester composition comprises about 92.8-95.6 wt. % of the at
least one copolyetherester, about 0.2-0.6 wt. % of the at least one
organic UV absorber, about 0.2-0.6 wt. % of the at least one hindered
amine light stabilizer, and about 4-6 wt. % of the mineral filler.

18. A light stabilized copolyetherester composition of claim 1, wherein,
the copolyetherester composition has a yellowness index change
(ΔYI) of less than about 2.3, or less than about 2, or less than
about 1.5 after 1500-hour aging.

19. An article formed from the light stabilized copolyetherester
composition recited in claim 1.

20. The article of claim 19, wherein the article is an insulating layer
or jacket for wires and cables.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from China National Patent
Application No. 201010538258.9, filed on Oct. 29, 2010, which is
incorporated herein by reference in its entirety.

[0003] Due to their excellent tear strength, tensile strength, flex life,
abrasion resistance, and suitability for a broad range of end-use
temperatures, thermoplastic copolyetherester elastomers are used in
numerous applications. However, copolyetheresters are known to be
particularly sensitive to ultraviolet (UV) radiation (see for example, F.
Gugumus in: R. Gachter, H. Muller (ed).; Plastics Additives Handbook,
3rd Ed., Hanser Publishers, Munich 1990, p. 170). Many outdoor
articles made of copolyetheresters are exposed to UV radiation during
their normal use. Organic UV light stabilizers are often added to such
copolyetherester compositions to improve their UV resistance and thereby
increasing the useful life of the articles made therefrom. Upon prolonged
exposure to UV radiation, however, typical organic UV light stabilizers
that have been used in copolyetherester compositions can degrade, leading
to a loss of physical properties of the copolyetherester compositions and
a diminished surface appearance of products made of the copolyetherester
compositions. It is also known to add inorganic UV light stabilizers,
such as carbon black, into copolyetherester compositions to improve their
UV resistance. However, an inevitable result of the addition of carbon
black is that the copolyetherester compositions will have a black or
near-black color. Therefore, carbon black is not suitable as a UV
stabilizer in those applications where the copolyetherester's natural
color or other non-black color is required.

[0004] Attempts have also been made to improve the UV resistance of
copolyetherester compositions that are free of carbon black. For example,
International Patent Application publication WO00/27914 discloses a thin
packaging film made of a thermoplastic material having UV resistance. The
thermoplastic material contains at least one organic UV-blocking compound
and at least one inorganic UV-blocking compound, wherein the inorganic
UV-blocking compound may be micronized zinc oxide or micronized titanium
dioxide. Also, U.S. Pat. No. 7,754,825 discloses a UV stabilized
copolyetherester composition that includes about 0.1-4 wt. % of at least
one nanoparticular mineral and about 0.1-4 wt. % of at least one organic
UV stabilizer, such as an hindered amine light stabilizer.

[0005] There is, however, still a need to further improve the UV
resistance of non-black copolyetherester compositions to meet the
requirements of outdoor applications.

SUMMARY OF THE INVENTION

[0006] The present invention is directed to a light stabilized
copolyetherester composition, which is substantially free of carbon black
and possesses good UV resistance, such as low yellowness index change
(ΔYI) after UV aging and high retention rate of nominal strain at
break after UV aging. Moreover, as the copolyetherester composition is
substantially free of carbon black, it is useful in forming articles
having natural or other non-black light colors.

[0007] Disclosed herein is a light stabilized copolyetherester composition
that is substantially free of carbon black, wherein the copolyetherester
composition comprises, based on the total weight of the copolyetherester
composition, (a) about 90-98.8 wt. % of at least one copolyetherester,
(b) about 0.1-2 wt. % of at least one organic UV absorber selected from
the group consisting of benzotriazole based UV absorbers and benzophenone
based UV absorber, (c) about 0.1-2 wt. % of at least one hindered amine
light stabilizer, and (d) about 1-6 wt. % of at least one mineral filler
comprising mineral particles selected from the group consisting of
titanium dioxide particles, cerium oxide particles, zinc oxide particles,
and mixtures of two or more thereof.

[0008] In one embodiment, the at least one copolyetherester comprises a
multiplicity of recurring long-chain ester units and recurring
short-chain ester units joined head-to-tail through ester linkages, the
long-chain ester units being represented by formula (I):

##STR00001##

[0009] and the short-chain ester units being represented by formula (II):

##STR00002##

[0010] wherein, [0011] G is a divalent radical remaining after the
removal of terminal hydroxyl groups from a poly(alkylene oxide) glycol
having a number average molecular weight of about 400-6000, or about
600-3000; [0012] R is a divalent radical remaining after the removal of
carboxyl groups from a dicarboxylic acid having a number average
molecular weight of about 300 or lower, or about 10-300, or about 30-200,
or about 50-100; and [0013] D is a divalent radical remaining after the
removal of hydroxyl groups from a glycol having a molecular weight of
about 250 or lower, or about 10-250, or about 20-150, or about 50-100,
and

[0014] wherein, [0015] based on the total weight of the at least one
copolyetherester, the content levels of the recurring long-chain ester
units and the recurring short-chain ester units are about 1-85 wt. % and
about 15-99 wt. %, respectively; or about 5-80 wt. % and about 20-95 wt.
%, respectively; or about 10-75 wt. % and about 25-90 wt. %,
respectively; or about 40-75 wt. % and about 25-60 wt. %, respectively.

[0016] In a further embodiment, the mineral particles have a weight
average particle diameter of about 10-200 nm, or about 30-175 nm, or
about 50-150 nm.

[0017] In a yet further embodiment, the mineral particles are titanium
dioxide particles.

[0018] In a yet further embodiment, the mineral particles are coated with
organic coatings or inorganic coatings. The organic coatings may comprise
a material selected from the group consisting of carboxylic acids,
polyols, alkanolamines, silicon compounds, and mixtures of two or more
thereof. The inorganic coatings may comprise a material selected from the
group consisting of oxides and hydrous oxides of silicon, aluminum,
zirconium, phosphorous, zinc, and rare earth elements, and mixtures of
two or more thereof. Or, the inorganic coatings may comprise alumina.

[0019] In a yet further embodiment, the at least one mineral filler
comprises titanium dioxide particles having a weight average particle
diameter of about 10-200 nm, or about 30-175 nm, or about 50-150 nm. The
titanium dioxide particles may be coated with alumina.

[0020] In a yet further embodiment, the at least one organic UV absorber
is selected from benzotriazole based UV absorbers.

[0021] In a yet further embodiment, based on the total weight of the
copolyetherester composition, the copolyetherester composition comprises
about 90-98.8 wt. % of the at least one copolyetherester, about 0.1-2 wt.
% of the at least one organic UV absorber, about 0.1-2 wt. % of the at
least one hindered amine light stabilizer, and about 1-6 wt. % of the
mineral filler.

[0022] In a yet further embodiment, based on the total weight of the
copolyetherester composition, the copolyetherester composition comprises
about 92-98.8 wt. % of the at least one copolyetherester, about 0.1-1 wt.
% of the at least one organic UV absorber, about 0.1-1 wt. % of the at
least one hindered amine light stabilizer, and about 1-6 wt. % of the
mineral filler.

[0023] In a yet further embodiment, based on the total weight of the
copolyetherester composition, the copolyetherester composition comprises
about 92-98.6 wt. % of the at least one copolyetherester, about 0.1-0.6
wt. % of the at least one organic UV absorber, about 0.1-0.6 wt. % of the
at least one hindered amine light stabilizer, and about 1-6 wt. % of the
mineral filler.

[0024] In a yet further embodiment, based on the total weight of the
copolyetherester composition, the copolyetherester composition comprises
about 92-97.8 wt. % of the at least one copolyetherester, about 0.1-1 wt.
% of the at least one organic UV absorber, about 0.1-1 wt. % of the at
least one hindered amine light stabilizer, and about 2-6 wt. % of the
mineral filler.

[0025] In a yet further embodiment, based on the total weight of the
copolyetherester composition, the copolyetherester composition comprises
about 92-95.8 wt. % of the at least one copolyetherester, about 0.1-1 wt.
% of the at least one organic UV absorber, about 0.1-1 wt. % of the at
least one hindered amine light stabilizer, and about 4-6 wt. % of the
mineral filler.

[0026] In a yet further embodiment, based on the total weight of the
copolyetherester composition, the copolyetherester composition comprises
about 92.8-95.6 wt. % of the at least one copolyetherester, about 0.2-0.6
wt. % of the at least one organic UV absorber, about 0.2-0.6 wt. % of the
at least one hindered amine light stabilizer, and about 4-6 wt. % of the
mineral filler.

[0027] In a yet further embodiment, the copolyetherester composition has a
yellowness index change (ΔYI) of less than about 2.3, or less than
about 2, or less than about 1.5 after 1500-hour aging.

[0028] Further disclosed herein is an article formed from the light
stabilized copolyetherester composition described above. In one
embodiment, the article is a molded article. In a further embodiment, the
article is an insulating layer or jacket for wires and cables.

DETAILED DESCRIPTION OF THE INVENTION

[0029] The invention disclosed herein provides a UV stabilized
copolyetherester composition that is substantially free of carbon black,
wherein the composition comprises, based on the total weight of the
composition, [0030] (a) about 90-98.8 wt. % of at least one
copolyetherester, [0031] (b) about 0.1-2 wt. % of at least one organic UV
absorber (UVA) selected from the group consisting of benzotriazole based
UVAs, benzophenone based UVAs, and mixtures thereof, [0032] (c) about
0.1-2 wt. % of at least one hindered amine light stabilizer (HALS); and
[0033] (d) about 1-6 wt. % of at least one mineral filler comprising
mineral particles selected from titanium dioxide particles, cerium oxide
particles, zinc oxide particles, and mixtures of two or more thereof.

[0034] The copolyetheresters suitable for use in the compositions
disclosed herein may be copolymers having a multiplicity of recurring
long-chain ester units and recurring short-chain ester units joined
head-to-tail through ester linkages, the long-chain ester units being
represented by formula (I):

##STR00003##

and the short-chain ester units being represented by formula (II):

##STR00004##

[0035] wherein,

[0036] G is a divalent radical remaining after the removal of terminal
hydroxyl groups from poly(alkylene oxide) glycols having a number average
molecular weight of about 400-6000;

[0037] R is a divalent radical remaining after the removal of carboxyl
groups from a dicarboxylic acid having a number average molecular weight
of about 300 or less;

[0038] D is a divalent radical remaining after the removal of hydroxyl
groups from a glycol having a number average molecular weight of about
250 or less, and

[0039] wherein,

[0040] the at least one copolyetherester contains about 1-85 wt. % of the
recurring long-chain ester units and about 15-99 wt. % of the recurring
short-chain ester units.

[0041] In one embodiment, the copolyetherester used in the composition
disclosed herein contains about 5-80 wt. % of the recurring long-chain
ester units and about 20-95 wt. % of the recurring short-chain ester
units.

[0042] In a further embodiment, the copolyetherester used in the
composition disclosed herein contains about 10-75 wt. % of the recurring
long-chain ester units and about 25-90 wt. % of the recurring short-chain
ester units.

[0043] In a yet further embodiment, the copolyetherester used in the
composition disclosed herein contains about 40-75 wt. % of the recurring
long-chain ester units and about 25-60 wt. % of the recurring short-chain
ester units.

[0044] As used herein, the term "long-chain ester units" refers to
reaction products of a long-chain glycol with a dicarboxylic acid.
Suitable long-chain glycols are poly(alkylene oxide) glycols having
terminal hydroxyl groups and a number average molecular weight of about
400-6000, or about 600-3000, which include, without limitation,
poly(tetramethylene oxide) glycol, poly(trimethylene oxide) glycol,
poly(propylene oxide) glycol, poly(ethylene oxide) glycol, copolymer
glycols of these alkylene oxides, and block copolymers such as ethylene
oxide-capped poly(propylene oxide) glycol. The long-chain glycols used
herein may also be combinations of two or more of the above glycols.

[0045] As used herein, the term "short-chain ester units" refers to
reaction products of a low molecular weight glycol or an ester-forming
derivative thereof with a dicarboxylic acid. Suitable low molecular
weight glycols are those having a number average molecular weight of
about 250 or lower, or about 10-250, or about 20-150, or about 50-100,
which include, without limitation, aliphatic dihydroxy compounds,
alicyclic dihydroxy compounds, and aromatic dihydroxy compounds
(including bisphenols). In one embodiment, the low molecular weight
glycol used herein is a dihydroxy compound having 2-15 carbon atoms, such
as ethylene glycol; propylene glycol; isobutylene glycol;
1,4-tetramethylene glycol; pentamethylene glycol;
2,2-dimethyltrimethylene glycol; hexamethylene glycol; decamethylene
glycol; dihydroxycyclohexane; cyclohexanedimethanol; resorcinol;
hydroquinone; 1,5-dihydroxynaphthalene; or the like. In a further
embodiment, the low molecular weight glycol used herein is a dihydroxy
compound having 2-8 carbon atoms. In a yet further embodiment, the low
molecular weight glycol used herein is 1,4-tetramethylene glycol.
Bisphenols that are useful herein include, without limitation,
bis(p-hydroxy)diphenyl, bis(p-hydroxyphenyl)methane,
bis(p-hydroxyphenyl)propane, and mixtures of two or more thereof.

[0046] The ester-forming derivatives of low molecular weight glycols
useful herein include those derived from the low molecular weight glycols
described above, such as ester-forming derivatives of ethylene glycol
(e.g., ethylene oxide or ethylene carbonate) or ester-forming derivatives
of resorcinol (e.g., resorcinol diacetate). As used herein, the number
average molecular weight limitations pertain to the low molecular weight
glycols only. Therefore, a compound that is an ester-forming derivative
of a glycol and has a number average molecular weight more than 250 can
also be used herein, provided that the corresponding glycol has a number
average molecular weight of about 250 or lower.

[0047] The "dicarboxylic acids" useful for reaction with the above
described long-chain glycols or low molecular weight glycols are those
low molecular weight (i.e., number average molecular weight of about 300
or lower, or about 10-300, or about 30-200, or about 50-100) aliphatic,
alicyclic, or aromatic dicarboxylic acids.

[0048] The term "aliphatic dicarboxylic acids" used herein refers to those
carboxylic acids having two carboxyl groups each attached to a saturated
carbon atom. If the carbon atom to which the carboxyl group is attached
to is saturated and is in a ring, the acid is referred to as an
"alicyclic dicarboxylic acid". The term "aromatic dicarboxylic acids"
used herein refers to those dicarboxylic acids having two carboxyl groups
each attached to a carbon atom in an aromatic ring structure. It is not
necessary that both functional carboxyl groups in the aromatic
dicarboxylic acid be attached to the same aromatic ring. Where more than
one ring is present, they can be joined by aliphatic or aromatic divalent
radicals or divalent radical such as --O-- or --SO2--.

[0051] In one embodiment of the compositions disclosed herein, the
dicarboxylic acids used to form the copolyetheresters component may be
selected from aromatic dicarboxylic acids. In a further embodiment, the
dicarboxylic acids may be selected from aromatic dicarboxylic acids
having about 8-16 carbon atoms. In a yet further embodiment, the
dicarboxylic acids may be terephthalic acid alone or a mixture of
terephthalic acid with phthalic acid and/or isophthalic acid.

[0052] In addition, the dicarboxylic acids useful herein may also include
functional equivalents of dicarboxylic acids. In forming the
copolyetheresters, the functional equivalents of dicarboxylic acids
reacts with the above described long-chain and low molecular weight
glycols substantially the same way as dicarboxylic acids. Useful
functional equivalents of dicarboxylic acids include ester and
ester-forming derivatives of dicarboxylic acids, such as acid halides and
anhydrides. As used herein, the number average molecular weight
limitations pertain only to the corresponding dicarboxylic acids, not the
functional equivalents thereof (such as the ester or ester-forming
derivatives thereof). Therefore, a compound that is a functional
equivalent of a dicarboxylic acid and has a number average molecular
weight more than 300 can also be used herein, provided that the
corresponding dicarboxylic acid has a number average molecular weight of
about 300 or lower. Moreover, the dicarboxylic acids may also contain any
substituent groups or combinations thereof that do not substantially
interfere with the copolyetherester formation and the use of the
copolyetherester in the compositions disclosed herein.

[0053] The long-chain glycols used in forming the copolyetherester
component of the composition disclosed herein may also be mixtures of two
or more long-chain glycols. Similarly, the low molecular weight glycols
and dicarboxylic acids used in forming the copolyetherester component may
also be mixtures of two or more low molecular weight glycols and mixtures
of two or more dicarboxylic acids, respectively. In a preferred
embodiment, at least about 70 mol % of the groups represented by R in
Formulas (I) and (II) above are 1,4-phenolene radicals, and at least 70
mol % of the groups represented by D in Formula (II) above are
1,4-butylene radicals. When two or more dicarboxylic acids are used in
forming the copolyetherester, it is preferred to use a mixture of
terephthalic acid and isophthalic acid, while when two or more low
molecular weight glycols are used, it is preferred to use a mixture of
1,4-tetramethylene glycol and hexamethylene glycol.

[0054] The at least one copolyetherester that is a component of the
copolyetherester composition disclosed herein may also be a blend of two
or more copolyetheresters. It is not required that the copolyetheresters
comprised in the blend, individually meet the weight percentages
requirements disclosed hereinbefore for the short-chain and long-chain
ester units. However, the blend of two or more copolyetheresters must
conform to the values described hereinbefore for the copolyetheresters on
a weighted average basis. For example, in a blend that contains equal
amounts of two copolyetheresters, one copolyetherester may contain about
10 wt. % of the short-chain ester units and the other copolyetherester
may contain about 80 wt. % of the short-chain ester units for a weighted
average of about 45 wt. % of the short-chain ester units in the blend.

[0055] In one embodiment, the at least one copolyetherester component of
the copolyetherester composition disclosed herein is obtained by the
copolymerization of a dicarboxylic acid ester selected from esters of
terephthalic acid, esters of isophthalic acid, and mixtures thereof, with
a lower molecular weight glycol that is 1,4-tetramethylene glycol and a
long-chain glycol that is poly(tetramethylene ether) glycol or ethylene
oxide-capped polypropylene oxide glycol. In a further embodiment, the at
least one copolyetherester is obtained by the copolymerization of an
ester of terephthalic acid (e.g., dimethylterephthalate) with
1,4-tetramethylene glycol and poly(tetramethylene ether) glycol.

[0056] The copolyetheresters useful in the compositions disclosed herein
may be made by any suitable methods known to those skilled in the art,
such as by using a conventional ester interchange reaction.

[0057] In one embodiment, the method involves heating an dicarboxylic acid
ester (e.g., dimethylterephthalate) with a poly(alkylene oxide) glycol
and a molar excess of a low molecular weight glycol (e.g.,
1,4-tetramethylene glycol) in the presence of a catalyst, followed by
distilling off methanol formed by the interchange reaction and continuing
the heat until methanol evolution is complete. Depending on the selection
of temperatures and catalyst types and the amount of the low molecular
weight glycols used, the polymerization may be completed within a few
minutes to a few hours and results in formation of a low molecular weight
pre-polymer. Such pre-polymers can also be prepared by a number of
alternate esterification or ester interchange processes, for example, by
reacting a long-chain glycol with a short-chain ester homopolymer or
copolymer in the presence of catalyst until randomization occurs. The
short-chain ester homopolymer or copolymer can be prepared by the ester
interchange either between a dimethyl ester (e.g., dimethylterephthalate)
and a low molecular weight glycol (e.g, 1,4-tetramethylene glycol) as
described above, or between a free acid (e.g., terephthalic acid) and a
glycol acetate (e.g., 1,4-butanediol diacetate). Alternatively, the
short-chain ester homopolymer or copolymer can be prepared by direct
esterification from appropriate acids (e.g., terephthalic acid),
anhydrides (e.g., phthalic anhydride), or acid chlorides (e.g.,
terephthaloyl chloride) with glycols (e.g., 1,4-tetramethylene glycol).
Or, the short-chain ester homopolymer or copolymer may be prepared by any
other suitable processes, such as the reaction of dicarboxylic acids with
cyclic ethers or carbonates.

[0058] Further, the pre-polymers obtained as described above can be
converted to high molecular weight copolyetheresters by the distillation
of the excess low molecular weight glycols. Such process is known as
"polycondensation". Additional ester interchange occurs during the
polycondensation process to increase the molecular weight and to
randomize the arrangement of the copolyetherester units. In general, to
obtained the best results, the polycondensation may be run at a pressure
of less than about 1 mm and a temperature of about 240-260° C., in
the presence of antioxidants (such as
1,6-bis-(3,5-di-tert-butyl-4-hydroxyphenol)propionamido]-hexane or
1,3,5-trimethyl-2,4,6-tris[3,5-di-tert-butyl-4-hydroxybenzyl]benzene),
and for less than about 2 hours. In order to avoid excessive holding time
at high temperatures with possible irreversible thermal degradation, it
is advantageous to employ a catalyst for ester interchange reactions. A
wide variety of catalysts can be used herein, which include, without
limitation, organic titanates (such as tetrabutyl titanate alone or in
combination with magnesium or calcium acetates), complex titanates (such
as those derived from alkali or alkaline earth metal alkoxides and
titanate esters), inorganic titanates (such as lanthanum titanate),
calcium acetate/antimony trioxide mixtures, lithium and magnesium
alkoxides, stannous catalysts, and mixtures of two or more thereof.

[0059] The copolyetheresters useful in the compositions disclosed herein
can also be obtained commercially from E.I. du Pont de Nemours and
Company, U.S.A. (hereafter "DuPont") under the tradename of Hytrel®.

[0060] Based on the total weight of the copolyetherester composition
disclosed herein, the at least one copolyetherester may be present at a
level of about 90-98.8 wt. %, or about 92-98.8 wt. %, or about 92-97.8
wt. %, or about 92-95.8 wt. %, or about 92.8-98.6 wt. %, or about
92.8-95.6 wt. %.

[0061] The at least one organic UVA comprised in the copolyetherester
composition disclosed herein may be selected from benzotriazole based
UVAs, benzophenone based UVAs, and mixtures thereof.

[0081] The at least one organic UVA may be present in the copolyetherester
composition disclosed herein at a level of about 0.1-2 wt. %, or about
0.1-1 wt. %, or about 0.2-0.6 wt. %, based on the total weight of the
copolyetherester composition.

[0082] In one embodiment, the copolyetherester composition disclosed
herein comprises about 0.1-2 wt. %, or about 0.1-1 wt. %, or about
0.2-0.6 wt. % of at least one benzotriazole based UVA.

[0083] The at least one HALS comprised in the copolyetherester composition
disclosed herein may be one or a combination of two or more HALS.

[0084] Suitable HALS may be selected from compounds having the following
general formulas:

[0094] The at least one HALS may be present in the copolyetherester
composition disclosed herein at a level of about 0.1-2 wt. %, or about
0.1-1 wt. %, or about 0.2-0.6 wt. %, based on the total weight of the
copolyetherester composition.

[0095] The mineral fillers useful in the copolyetherester compositions
disclosed herein comprise mineral particles selected from titanium oxide
particles, cerium oxide particles, zinc oxide particles, and mixtures of
two or more thereof. In one embodiment, the mineral particles comprised
in the mineral fillers are nanosized mineral particles. In a further
embodiment, the mineral particles are nanosized mineral particles having
a weight average particle diameter of about 10-200 nm, or about 30-175
nm, or about 50-150 nm. The mineral fillers may also comprise other
additional additives to improve the durability characteristics or other
properties of the fillers. For example, such additional additives may
include, without limitation, hydrous oxides (such as silica, alumina, tin
oxide, lead oxide, chromium oxides) and the like.

[0096] In one embodiment, the mineral fillers used herein comprise
titanium dioxide particles.

[0097] In a further embodiment, the mineral fillers used herein comprise
nanosized titanium dioxide particles having a weight average particle
diameter of about 10-200 nm, or about 30-175 nm, or about 50-150 nm.

[0098] In accordance with the present disclosure, the mineral particles
comprised in the mineral fillers may also be coated with organic and/or
inorganic coatings.

[0099] Suitable inorganic coatings may be formed of inorganic materials
selected from, without limitation, metal oxides and hydrous oxides, such
as oxides and hydrous oxides of silicon, aluminum, zirconium,
phosphorous, zinc, rare earth elements, and mixtures of two or more
thereof. In one embodiment, the inorganic coating used herein may be
formed of alumina.

[0100] Suitable organic coatings may by formed of organic materials
selected from, without limitation, carboxylic acids, polyols,
alkanolamines, silicon compounds, and mixtures of two or more thereof.
Suitable carboxylic acids used in forming the organic coatings include,
without limitation, adipic acid, terephthalic acid, lauric acid, myristic
acid, palmitic acid, stearic acid, polyhydroxystearic acid, oleic acid,
salicylic acid, malic acid, maleic acid, and mixtures of two or more
thereof. As used herein, the "carboxylic acids" used in forming the
organic coatings may also include esters of the carboxylic acids
mentioned immediately above, salts of the carboxylic acids immediately
mentioned above, and mixtures thereof. Suitable polyols include, without
limitation, ethylene glycol, propylene glycol, butanediol, hexanediol,
and mixtures of two or more thereof. Suitable alkanolamines include,
without limitation, ethanolamine, ethylene glycol amine, propanol amine,
propylene glycol amine, and mixtures of two or more thereof. Suitable
silicon compounds include, without limitation, silicates, silanes (e.g.,
organoalkoxysilanes, aminosilanes, epoxysilanes, and mercaptosilanes),
siloxanes (e.g., polyhydroxysiloxanes), and mixtures of two or more
thereof. In one embodiment, the silanes used in forming the organic
coatings have a formula of RxSi(R')4-x wherein R is a
nonhydrolyzable aliphatic, cycloaliphatic, or aromatic group having about
1-20 carbon atoms, R' is one or more hydrolyzable groups (e.g., one or
more alkoxy, halogen, acetoxy, and/or hydroxy groups), and X is 1, 2 or
3. In a further embodiment, the silanes used in forming the organic
coatings are selected from hexyltrimethoxysilane, octyltriethoxysilane,
nonyltriethoxysilane, decyltriethoxysilane, dodecyltriethoxysilane,
tridecyltriethoxysilane, tetradecyltriethoxysilane,
pentadecyltriethoxysilane, hexadecyltriethoxysilane,
heptadecyltriethoxysilane, octadecyltriethoxysilane, N-(2-aminoethyl)
3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)
3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane,
3-glycidoxypropyltrimethoxysilane,
3-glycidoxypropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane,
and combinations of two or more thereof.

[0101] In one embodiment, the mineral particles (e.g., titanium dioxide
particles or nanosized titanium dioxide particles) comprised in the
mineral fillers are coated with an inorganic coating (e.g., alumina). In
addition, the mineral particles that are coated with inorganic coatings
may be further coated with other coatings (e.g., an organic coating).

[0102] When present, the organic coatings may comprise about 0.1-10 wt. %
or about 0.5-7 wt. %, or about 0.5-5 wt. % of the total weight of the
mineral fillers, while the inorganic coatings may comprise about 0.25-50
wt. %, or about 1-25 wt. %, or about 2-20 wt. % of the total weight of
the mineral fillers.

[0103] The mineral particles (e.g., titanium dioxide particles) comprised
in the mineral fillers may be prepared by any suitable method known to
those skilled in the art. Additionally, phosphoric acid, metal
phosphates, metal halides, metal carbonates, metal sulfates, and
combinations of two or more thereof may be used to control the
crystallinity, degree of amorphousness, or millability of the particles.
Suitable metals for the foregoing include sodium, potassium, aluminum,
tin, or zinc.

[0104] Based on the total weight of the copolyetherester composition
disclosed herein, the at least one mineral filler may be present at a
level of about 1-6 wt. %, or about 2-6 wt. %, or about 4-6 wt. %.

[0106] However, the copolyetherester composition disclosed herein is
substantially free of carbon black. The term "substantially free of
carbon black" used herein refers to a content level of carbon black being
less than about 0.1 wt. %, based on the total weight of the
copolyetherester composition.

[0107] In one embodiment, based on the total weight of the
copolyetherester composition disclosed herein, the at least one
copolyetherester, the at least one organic UVA, the at least one HALS,
and the at least one mineral filler are present in amounts of, [0108]
about 90-98.8 wt. %, about 0.1-2 wt. %, about 0.1-2 wt. %, and about 1-6
wt. %, respectively; or [0109] about 92-98.8 wt %, about 0.1-1 wt,%,
about 0.1-1 wt,%, and about 1-6 wt, %, respectively; or [0110] about
92.8-98.6 wt. %, about 0.2-0.6 wt. %, about 0.2-0.6 wt. %, and about 1-6
wt. %, respectively; or [0111] about 92-97.8 wt. %, about 0.1-1 wt. %,
about 0.1-1 wt. %, and about 2-6 wt. %, respectively; or [0112] about
92-95.8 wt. %, about 0.1-1 wt. %, about 0.1-1 wt. %, and about 4-6 wt. %,
respectively; or [0113] about 92.8-95.6 wt. %, about 0.2-0.6 wt. %, about
0.2-0.6 wt. %, and about 4-6 wt. %, respectively.

[0114] The copolyetherester compositions disclosed herein are melt-mixed
blends, wherein all of the polymeric components are well-dispersed within
each other and all of the non-polymeric ingredients are homogeneously
dispersed in and bound by the polymer matrix, such that the blend forms a
unified whole. Any melt-mixing method may be used to combine the
polymeric components and non-polymeric ingredients of the composition
disclosed herein.

[0115] In one embodiment, during the melt mixing process, the mineral
fillers are added in the form of masterbatches, wherein the masterbatches
are prepared by dispersing high concentration of mineral particles in a
polymer matrix such as a copolyetherester.

[0116] In a further embodiment, the melt-mixing process involves, adding
the polymeric components and the non-polymeric ingredients all at once or
in a stepwise fashion into a melt mixer (such as, for example, a single
or twin-screw extruder; a blender; a kneader; or a Banbury mixer) and
then melt-mixing the blend. When adding the polymeric components and the
non-polymeric ingredients in a stepwise fashion, part of the polymeric
components and/or part of the non-polymeric ingredients are first added
and melt-mixed, with the remaining polymeric components and the remaining
non-polymeric ingredients being subsequently added and further melt-mixed
until a well-mixed composition is obtained.

[0117] As demonstrated by the examples below, in the presence of both
organic UVA (i.e., benzotriazole and/or benzophenone based UVA) and HALS,
the addition of mineral fillers (e.g., titanium dioxide particles)
improves the retention rate of nominal strain at break (after aging) of
the copolyetherester composition. Moreover, it has been demonstrated that
with the addition of such a three-component UV stabilizing package (i.e.,
organic UVA; HALS; and mineral fillers), the yellowness index change
(ΔYI) of the copolyetherester composition after aging is
dramatically decreased. Therefore, compared to prior art copolyetherester
compositions, the copolyetherester compositions disclosed herein (i.e.,
the copolyetherester compositions containing the three-component UV
stabilizing package), possess not only improved physical properties
(e.g., nominal strain at break) but also less discoloration after aging.
In addition, because they are substantially free of carbon black, the
copolyetherester compositions disclosed herein are suitable for forming
products of natural or light color.

[0118] In accordance, the copolyetherester composition disclosed herein
may have a ΔYI of less than about 2.3, or less than about 2, or
less than about 1.5 after 1500-hour aging. The ΔYI disclosed herein
is determined in accordance to ASTM E313 and the 1500-hour aging is
conducted in accordance to ISO4892-2 with the chamber temperature set at
38±3° C., black standard temperature at 65±3° C.,
relative humidity at 50±10%, and irradiation intensity at 0.51
w/m2 (at wavelength of 340 nm).

[0119] The copolyetherester compositions disclosed herein may be formed
into articles using methods known to those skilled in the art, such as,
for example, injection molding, blow molding, extrusion, thermoforming,
melt casting, rotational molding, and slush molding. The copolyetherester
compositions may be overmolded onto articles made from different
materials. The copolyetherester compositions may be extruded into films.
The copolyetherester compositions may be formed into monofilaments. The
copolyetherester compositions may also be extruded into insulating layers
or jackets for wires and cables.

[0124][0125] Nominal strain at break: Copolyetherester compositions
were molded into dumbbell test bar specimens and the nominal strain at
break thereof were determined in accordance with ISO527-2. [0126]
Yellowness Index (YI): Copolyetherester compositions were molded into
60×60×2 mm plaques and the YI thereof was determined in
accordance with ASTM E313 using an X-rite 8200 spectrophotometer
(purchased from X-rite Corporation, U.S.A.). [0127] Aging: Aging tests
were performed in accordance with ISO4892-2 using a Ci4000 weatherometer
(purchased from Atlas Material Testing Solutions, U.S.A.). During the
aging process, the chamber temperature was set at 38±3° C.,
black standard temperature at 65±3° C., relative humidity at
50±10%, and irradiation intensity at 0.51 w/m2 (at wavelength of
340 nm). The aging process included alternate 102 minute dry cycles and
18 minute spray cycles.

Test Results:

[0128] All components contained in each of the copolyetherester
compositions in Examples E1 and Comparative Examples CE1-2 and the
amounts present are listed in Table 1 below. The compositions used in E1
and CE1-2 were prepared as follows. A TiO2 masterbatch comprising 35
wt. % TiO2 and 65 wt. % Copolyetherester was prepared using a ZSK-30
twin-screw extruder (purchased from Coperion Werner & Pfleiderer GmbH &
Co., Germany) with the extruder temperature set at 150-230° C.,
the extrusion speed at 300 rpm, and the throughput at 30 lb/hr.
Appropriate amounts of Copolyetherester, TiO2 masterbatch, UVA, and
HALS were then dried, pre-mixed, and melt blended in a ZSK26 twin-screw
extruder (purchased from Coperion Werner & Pfleiderer GmbH & Co.,
Germany) with the extruder temperature set at 220-235° C., the
extrusion speed at 300 rpm, and the throughput at 20 kg/hr, to obtain the
copolyetherester compositions.

[0129] Each of the copolyetherester compositions used in E1 and CE1-2 were
molded into dumbbell test bar specimens and the nominal strain at break
thereof were determined as described above and tabulated in Table 1. The
test bar specimens were then aged for 100 hours, 200 hours, 500 hours,
1000 hours, or 1500 hours and the nominal strain at break thereof after
aging were determined as described above and tabulated in Table 1.
Thereafter, the "retention rate of nominal strain at break" of the
compositions after aging were calculated and tabulated in Table 1.

[0130] In addition, each of the copolyetherester compositions used in E1
and CE1-2 was molded into a 60×60×2 mm plaque and the YI
thereof was determined as described above and tabulated in Table 1. The
plaques were then aged for 100 hours, 200 hours, 500 hours, 1000 hours,
or 1500 hours and the YI thereof after aging were determined as described
above and tabulated in Table 1. Thereafter, the "Yellowness Index Change
(ΔYI)" of the compositions after aging was calculated and tabulated
in Table 1.

[0131] The results demonstrate that when TiO2 is added to
copolyetherester compositions, in the presence of both UVA and HALS, not
only is the retention of nominal strain at break (after aging) of the
compositions is improved, the yellowness index change (ΔYI) (after
aging) of the compositions is also largely reduced.